Colloquium- Eric Borguet (Temple University)-Structure and ultrafast dynamics at aqueous-oxide interfaces

April 6, 2023

1:15PM - 2:15PM

4138 Physics Research Building

Add to Calendar 2023-04-06 13:15:00 2023-04-06 14:15:00 Colloquium- Eric Borguet (Temple University)-Structure and ultrafast dynamics at aqueous-oxide interfaces Dr. Eric Borguet Temple University Structure and ultrafast dynamics at aqueous-oxide interfaces Location: 4138 Physics Research Building Faculty Host: Louis DiMauro & Sherwin Singer Abstract: Interfacial water structure is key to diverse chemical and physical processes, including many of environmental and geochemical relevance. It can be probed by vibrational sum-frequency generation (vSFG) spectroscopy as well as ultrafast time-resolved vSFG. However, a more complete microscopic understanding requires additional techniques such as molecular dynamics simulations. Our experiments show that in the absence of surface charge (pH 2), water at silica surfaces exhibits significantly slower OH stretch vibrational relaxation (~600 fs) compared to bulk water. However, at charged silica surfaces (e.g., pH 6), bulk-like fast dynamics (~200 fs) are observed at low ionic strength. This decelerates to ~600 fs with the addition of NaCl. In parallel, vSFG results demonstrated that silica interfacial water structure is most sensitive to ions at pH=6-8, correlating with the known salt and pH dependence of silica surface reactivity. Consequently, it is unclear whether the observed slowing of the vibrational dynamics is due to the reduction in the Debye length, or because of changes in the local hydrogen bonding environment caused by the electrolyte and how this might depend on the identity of the ions or the solid surface. The combination of molecular dynamics simulations with spectroscopic and time-resolved vSFG experiments on aqueous Al2O3 interfaces, along with the use of a molecular probe SCN-, sheds light on the ongoing debate on the role of ions in interfacial water structure and whether the observed behavior is specific to silica/water interfaces or can be generalized to other aqueous interfaces. Bio: Dr. Eric Borguet is the Hazel Tomlinson Professor of Chemistry at Temple University in Philadelphia, PA. He was born in Dublin, Ireland, where he spent his formative years. He attended college in France at the Université de Paris-Sud (XI-Orsay) where he studied chemistry and physics. He traveled to Philadelphia, Pennsylvania in the USA and obtained his Ph.D. in Physical Chemistry at the University of Pennsylvania in 1993, under the mentorship of Professor Hai-Lung Dai where he investigated adsorption and intermolecular interaction on stepped metal surfaces. His post-doctoral training was completed at Columbia University in the group of Professor Kenneth Eisenthal using nonlinear optics to investigate spectroscopy and ultrafast dynamics at liquid interfaces. Chemical and physical processes at surfaces and interfaces are the principal focus of his ongoing research program at Temple University. His research activities have resulted in over 150 peer-reviewed publications, in excess of 300 invited talks and more than 270 contributed presentations. Eric has mentored 30 graduate students, 21 of whom earned a Ph.D. and went on to post-doctoral fellowships, as well as industrial and academic careers. He has advised over 100 undergraduate researchers, many of whom have continued to graduate studies. His group has welcomed 16 visiting graduate students, as well as 5 sabbatical visiting scholars. He has supervised the training of 19 post-doctoral fellows. Google Scholar Publications Current Research themes: Nonlinear Optics and Ultrafast Processes at Interfaces Development of Ultrafast Optical Parametric Amplifiers Electrical conductivity in Single Molecules Nanomaterial Synthesis and Characterization Nanoscale Dynamics at Interfaces Surface Mediated Sensors Plasmonics Honors and Awards: Inaugural Hazel Tomlinson Professor of Chemistry 2023-present Morino Lectureship, Japan 2019-2020 Honorary Visiting Professor, Indian Institute of Technology-Bombay, India 2019-2020 Fullbright Specialist Roster, 2018-2023 Visiting Professor, Université Paul Sabatier, Toulouse, France 2013 Temple CST Dean’s Distinguished Excellence in Mentoring Award, 2012 Visiting Professor, Hokkaido University, Japan 2012 American Physical Society Fellow, 2010 American Chemical Society, Philadelphia Section Award, 2009 U.S. Young Observer to 2007 IUPAC General Assembly and Congress, 2007 Visiting Fellow, Japan Society for the Promotion of Science, 2007-2008 Visiting Professor, Université de Bordeaux, France 1999 NSF- CAREER Award, 1998-2002 Dr. Eric Borguet’s CV Department of Chemistry 130 Beury Hall Temple University 1901 N. 13th Street Philadelphia, PA 19122 Office: 1 (215) 204-9696, Room 252 eborguet@temple.ed 4138 Physics Research Building OSU ASC Drupal 8 ascwebservices@osu.edu America/New_York public

Add to Calendar 2023-04-06 13:15:00 2023-04-06 14:15:00 Colloquium- Eric Borguet (Temple University)-Structure and ultrafast dynamics at aqueous-oxide interfaces Dr. Eric Borguet Temple University Structure and ultrafast dynamics at aqueous-oxide interfaces  Location: 4138 Physics Research Building  Faculty Host: Louis DiMauro &  Sherwin Singer    Abstract: Interfacial water structure is key to diverse chemical and physical processes, including many of environmental and geochemical relevance.  It can be probed by vibrational sum-frequency generation (vSFG) spectroscopy as well as ultrafast time-resolved vSFG.  However, a more complete microscopic understanding requires additional techniques such as molecular dynamics simulations.  Our experiments show that in the absence of surface charge (pH 2), water at silica surfaces exhibits significantly slower OH stretch vibrational relaxation (~600 fs) compared to bulk water.  However, at charged silica surfaces (e.g., pH 6), bulk-like fast dynamics (~200 fs) are observed at low ionic strength.  This decelerates to ~600 fs with the addition of NaCl.  In parallel, vSFG results demonstrated that silica interfacial water structure is most sensitive to ions at pH=6-8, correlating with the known salt and pH dependence of silica surface reactivity.  Consequently, it is unclear whether the observed slowing of the vibrational dynamics is due to the reduction in the Debye length, or because of changes in the local hydrogen bonding environment caused by the electrolyte and how this might depend on the identity of the ions or the solid surface.  The combination of molecular dynamics simulations with spectroscopic and time-resolved vSFG experiments on aqueous Al2O3 interfaces, along with the use of a molecular probe SCN-, sheds light on the ongoing debate on the role of ions in interfacial water structure and whether the observed behavior is specific to silica/water interfaces or can be generalized to other aqueous interfaces.    Bio: Dr. Eric Borguet is the Hazel Tomlinson Professor of Chemistry at Temple University in Philadelphia, PA. He was born in Dublin, Ireland, where he spent his formative years. He attended college in France at the Université de Paris-Sud (XI-Orsay) where he studied chemistry and physics. He traveled to Philadelphia, Pennsylvania in the USA and obtained his Ph.D. in Physical Chemistry at the University of Pennsylvania in 1993, under the mentorship of Professor Hai-Lung Dai where he investigated adsorption and intermolecular interaction on stepped metal surfaces. His post-doctoral training was completed at Columbia University in the group of Professor Kenneth Eisenthal using nonlinear optics to investigate spectroscopy and ultrafast dynamics at liquid interfaces. Chemical and physical processes at surfaces and interfaces are the principal focus of his ongoing research program at Temple University. His research activities have resulted in over 150 peer-reviewed publications, in excess of 300 invited talks and more than 270 contributed presentations. Eric has mentored 30 graduate students, 21 of whom earned a Ph.D. and went on to post-doctoral fellowships, as well as industrial and academic careers. He has advised over 100 undergraduate researchers, many of whom have continued to graduate studies. His group has welcomed 16 visiting graduate students, as well as 5 sabbatical visiting scholars. He has supervised the training of 19 post-doctoral fellows. Google Scholar Publications Current Research themes: Nonlinear Optics and Ultrafast Processes at Interfaces Development of Ultrafast Optical Parametric Amplifiers Electrical conductivity in Single Molecules Nanomaterial Synthesis and Characterization Nanoscale Dynamics at Interfaces Surface Mediated Sensors Plasmonics Honors and Awards: Inaugural Hazel Tomlinson Professor of Chemistry 2023-present Morino Lectureship, Japan 2019-2020 Honorary Visiting Professor, Indian Institute of Technology-Bombay, India 2019-2020 Fullbright Specialist Roster, 2018-2023 Visiting Professor, Université Paul Sabatier, Toulouse, France 2013 Temple CST Dean’s Distinguished Excellence in Mentoring Award, 2012 Visiting Professor, Hokkaido University, Japan 2012 American Physical Society Fellow, 2010 American Chemical Society, Philadelphia Section Award, 2009 U.S. Young Observer to 2007 IUPAC General Assembly and Congress, 2007 Visiting Fellow, Japan Society for the Promotion of Science, 2007-2008                                          Visiting Professor, Université de Bordeaux, France 1999                                                                                  NSF- CAREER Award, 1998-2002 Dr. Eric Borguet’s CV Department of Chemistry 130 Beury Hall Temple University 1901 N. 13th Street Philadelphia, PA 19122 Office: 1 (215) 204-9696, Room 252 eborguet@temple.ed 4138 Physics Research Building Department of Physics physics@osu.edu America/New_York public

Dr. Eric Borguet

Temple University

Structure and ultrafast dynamics at aqueous-oxide interfaces

Location: 4138 Physics Research Building

Faculty Host: Louis DiMauro & Sherwin Singer

Abstract: Interfacial water structure is key to diverse chemical and physical processes, including many of environmental and geochemical relevance. It can be probed by vibrational sum-frequency generation (vSFG) spectroscopy as well as ultrafast time-resolved vSFG. However, a more complete microscopic understanding requires additional techniques such as molecular dynamics simulations. Our experiments show that in the absence of surface charge (pH 2), water at silica surfaces exhibits significantly slower OH stretch vibrational relaxation (~600 fs) compared to bulk water. However, at charged silica surfaces (e.g., pH 6), bulk-like fast dynamics (~200 fs) are observed at low ionic strength. This decelerates to ~600 fs with the addition of NaCl. In parallel, vSFG results demonstrated that silica interfacial water structure is most sensitive to ions at pH=6-8, correlating with the known salt and pH dependence of silica surface reactivity. Consequently, it is unclear whether the observed slowing of the vibrational dynamics is due to the reduction in the Debye length, or because of changes in the local hydrogen bonding environment caused by the electrolyte and how this might depend on the identity of the ions or the solid surface. The combination of molecular dynamics simulations with spectroscopic and time-resolved vSFG experiments on aqueous Al₂O₃ interfaces, along with the use of a molecular probe SCN^-, sheds light on the ongoing debate on the role of ions in interfacial water structure and whether the observed behavior is specific to silica/water interfaces or can be generalized to other aqueous interfaces.

Structure and ultrafast dynamics at aqueous-oxide interfaces

Bio: Dr. Eric Borguet is the Hazel Tomlinson Professor of Chemistry at Temple University in Philadelphia, PA. He was born in Dublin, Ireland, where he spent his formative years. He attended college in France at the Université de Paris-Sud (XI-Orsay) where he studied chemistry and physics. He traveled to Philadelphia, Pennsylvania in the USA and obtained his Ph.D. in Physical Chemistry at the University of Pennsylvania in 1993, under the mentorship of Professor Hai-Lung Dai where he investigated adsorption and intermolecular interaction on stepped metal surfaces. His post-doctoral training was completed at Columbia University in the group of Professor Kenneth Eisenthal using nonlinear optics to investigate spectroscopy and ultrafast dynamics at liquid interfaces.

Chemical and physical processes at surfaces and interfaces are the principal focus of his ongoing research program at Temple University. His research activities have resulted in over 150 peer-reviewed publications, in excess of 300 invited talks and more than 270 contributed presentations.

Eric has mentored 30 graduate students, 21 of whom earned a Ph.D. and went on to post-doctoral fellowships, as well as industrial and academic careers. He has advised over 100 undergraduate researchers, many of whom have continued to graduate studies. His group has welcomed 16 visiting graduate students, as well as 5 sabbatical visiting scholars. He has supervised the training of 19 post-doctoral fellows.

Google Scholar Publications

Current Research themes:
Nonlinear Optics and Ultrafast Processes at Interfaces
Development of Ultrafast Optical Parametric Amplifiers
Electrical conductivity in Single Molecules
Nanomaterial Synthesis and Characterization
Nanoscale Dynamics at Interfaces
Surface Mediated Sensors
Plasmonics

Honors and Awards:

Inaugural Hazel Tomlinson Professor of Chemistry 2023-present
Morino Lectureship, Japan 2019-2020
Honorary Visiting Professor, Indian Institute of Technology-Bombay, India 2019-2020
Fullbright Specialist Roster, 2018-2023
Visiting Professor, Université Paul Sabatier, Toulouse, France 2013
Temple CST Dean’s Distinguished Excellence in Mentoring Award, 2012
Visiting Professor, Hokkaido University, Japan 2012
American Physical Society Fellow, 2010
American Chemical Society, Philadelphia Section Award, 2009
U.S. Young Observer to 2007 IUPAC General Assembly and Congress, 2007
Visiting Fellow, Japan Society for the Promotion of Science, 2007-2008 Visiting Professor, Université de Bordeaux, France 1999 NSF- CAREER Award, 1998-2002

Dr. Eric Borguet’s CV

Department of Chemistry
130 Beury Hall
Temple University
1901 N. 13th Street
Philadelphia, PA 19122
Office: 1 (215) 204-9696, Room 252
eborguet@temple.ed